Metal capacitor

ABSTRACT

A metal capacitor provided includes a first metal layer and a second metal layer disposed above a substrate. The first metal layer includes a first electrode sheet and a second electrode sheet, and the second metal layer includes a third electrode sheet and a fourth electrode sheet. The first electrode sheet and the second electrode sheet collectively form a first coplanar capacitor. The third electrode sheet and the fourth electrode sheet collectively form a second coplanar capacitor. At least a portion of the fourth electrode sheet is arranged above the first electrode sheet, and the first electrode sheet and the fourth electrode sheet collectively form a first vertical capacitor. At least a portion of the third electrode sheet is arranged above the second electrode sheet, and the second electrode sheet and the third electrode sheet collectively form a second vertical capacitor.

This is a Continuation of U.S. application Ser. No. 16/784,292, filedFeb. 7, 2020, now U.S. Pat. No. 11,152,458, the subject matter of whichis incorporated herein by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The invention relates in general to a metal capacitor, and moreparticularly to a metal capacitor taking advantage of parasiticcapacitance.

Description of the Related Art

In an analog circuit, the operating voltage required for the internalcircuit is usually higher than the supply voltage Vdd received by thesystem. For example, a memory circuit receives a supply voltage Vdd of3V, but the select operation, write operation and erase operation of thememory circuit may require higher voltages of 5V, 10V and 12V,respectively. Therefore, a charge pump is usually provided in the analogcircuit to generate the operating voltage when the supply voltage (forexample, battery voltage) is not high enough.

Please refer to FIG. 1 , which is a circuit diagram of a voltagemultiplier circuit. The voltage multiplier circuit 10 includes a cascadeof charge pumps 10 a. While being driven by the clock signals clk andclkb in antiphase alternately, each later-stage charge pump 10 agenerates a higher voltage. The quantity of the charge pumps 10 aincluded in the voltage multiplier circuit 10 is determined according tothe supply voltage Vdd and the output voltage Vout.

In FIG. 1 , each charge pump 10 a includes two inverters connected inseries, a boot capacitor Cb and a diode-wired passmetal-oxide-semiconductor field-effect transistor (MOSFET). Twoterminals of the boot capacitor Cb receive the boost voltage Vb and thedriving clock signal clkd, respectively. In the charge pump 10 a, theboot capacitor Cb occupies many areas. Therefore, it is desired toreduce the area of the boot capacitor Cb to cut down the productioncost.

SUMMARY OF THE INVENTION

The invention is directed to a metal capacitor taking advantage ofparasitic capacitance occurring on dummy metal layers. This metalcapacitor could be used with a MOS capacitor to increase the capacitancewithout additional area.

According to one aspect of the present invention, a metal capacitor isprovided. The metal capacitor includes a first metal layer and a secondmetal layer. The first metal layer is disposed above a substrate, andthe second metal layer is disposed above the first metal layer. Thefirst metal layer includes a first electrode sheet and a secondelectrode sheet, both of which collectively form a first coplanarcapacitor. The second metal layer includes a third electrode sheet and afourth electrode sheet, both of which collectively form a secondcoplanar capacitor. At least a portion of the fourth electrode sheet isarranged above the first electrode sheet, and the first electrode sheetand the fourth electrode sheet collectively form a first verticalcapacitor. At least a portion of the third electrode sheet is arrangedabove the second electrode sheet, and the second electrode sheet and thethird electrode sheet collectively form a second vertical capacitor.

According to another aspect of the present invention, a metal capacitoris provided. The metal capacitor includes at least one metal layerdisposed above a metal-oxide-semiconductor capacitor. The metal layerincludes a first electrode sheet and a second electrode sheet. The firstelectrode sheet receives a first voltage, and the second electrode sheetreceives a second voltage.

The above and other aspects of the invention will become betterunderstood with regard to the following detailed description of thepreferred but non-limiting embodiment(s). The following description ismade with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 (prior art) is a circuit diagram of a voltage multiplier circuit.

FIG. 2 is a circuit diagram showing the metal capacitor C_MET and theMOS capacitor C_MOS connected in parallel.

FIG. 3 is a schematic diagram illustrating an electrode pattern on themetal layer disposed above the MOS capacitor.

FIG. 4 is a schematic diagram illustrating that electrode sheets areformed of two metal layers, and the capacitance is formed based on theelectrode patterns of the electrode sheets according to an embodiment ofthe present disclosure.

FIGS. 5A, 5B, 5C, and 5D are schematic diagrams showing the mutualcapacitance between the electrode sheets of the two metal layers.

FIG. 6 is a schematic diagram illustrating the configuration of theelectrode sheet ELED1.

FIG. 7 is a schematic diagram illustrating the components of theelectrode pattern of the electrode sheet ELED1.

FIG. 8 is a schematic diagram illustrating the configuration of theelectrode sheet ELED2.

FIG. 9 is a schematic diagram illustrating the components of theelectrode pattern of the electrode sheet ELED2.

FIG. 10 is a schematic diagram illustrating that the electrode sheetELED1 in FIG. 6 , and the electrode sheet ELED2 in FIG. 8 are combinedto provide the metal layer MTL1.

FIG. 11 is a schematic diagram illustrating the configuration of theelectrode sheet ELED3.

FIG. 12 is a schematic diagram illustrating the components of theelectrode pattern of the electrode sheet ELED3.

FIG. 13 is a schematic diagram illustrating the configuration of theelectrode sheet ELED4.

FIG. 14 is a schematic diagram illustrating the components of theelectrode pattern of the electrode sheet ELED4.

FIG. 15 is a schematic diagram illustrating that the electrode sheetELED3 in FIG. 11 and the electrode sheet ELED4 in FIG. 13 are combinedto provide the metal layer MTL2.

FIG. 16 is a schematic diagram illustrating that the electrode patternson the multiple metal layers are arranged in an alternate manner.

FIG. 17 is a schematic diagram illustrating that the capacitance effectbetween electrode sheets of two metal layers occurs based on theelectrode patterns of the electrode sheets according to anotherembodiment of the present disclosure.

FIG. 18 is a schematic diagram illustrating that the electrode sheets ofthe metal layer s2MTL1 include two sections according to a furtherembodiment of the present disclosure.

FIG. 19 is a schematic diagram illustrating the configuration of theelectrode sheet s2ELED1 in FIG. 18 .

FIG. 20 is a schematic diagram illustrating the components of theelectrode pattern of the electrode sheet s2ELED1 in FIG. 18 .

FIG. 21 is a schematic diagram illustrating the configuration of theelectrode sheet s2ELED2 in FIG. 18 .

FIG. 22 is a schematic diagram illustrating the components of theelectrode pattern of the electrode sheet s2ELED2 in FIG. 18 .

FIG. 23 is a schematic diagram illustrating that the electrode sheets ofthe metal layer s2MTL1′ includes two sections according to a furtherembodiment of the present disclosure.

FIG. 24 is a schematic diagram illustrating the configuration of theelectrode sheet s2ELED1′ in FIG. 23 .

FIG. 25 is a schematic diagram illustrating the components of theelectrode pattern of the electrode sheet s2ELED1′ in FIG. 23 .

FIG. 26 is a schematic diagram illustrating the configuration of theelectrode sheet s2ELED2′ in FIG. 23 .

FIG. 27 is a schematic diagram illustrating the components of theelectrode pattern of the electrode sheet s2ELED2′ in FIG. 23 .

FIG. 28 is a schematic diagram illustrating that the electrode sheets ofthe metal layer s4MTL1 include four sections according to a furtherembodiment of the present disclosure.

FIG. 29 is a schematic diagram illustrating that the electrode sheets ofthe metal layer s4MTL1′ includes four sections according to a furtherembodiment of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

MOS capacitors are widely used in semiconductor devices, but the MOScapacitors occupy larger areas. Therefore, it is an important issue toreduce the area of the boot capacitors Cb in the semiconductor circuits.For illustration purposes, the capacitor implemented by a MOSFET isreferred to as MOS capacitor C_MOS hereinafter.

In a memory circuit, many metal layers are formed for access to memorycells. These metal layers are provided mainly for the control of thememory cell circuits, but these metal layers located in the non-memorycell circuits (for example, MOS capacitors C_MOS in the charge pumps)are unused. In other words, the metal layers disposed above the MOScapacitors C_MOS are unused. Accordingly, the present disclosuretransforms the unused dummy metal layers above the MOS capacitors C_MOSinto metal capacitors C_MET. The metal capacitors C_MET are connected tothe MOS capacitors C_MOS in parallel to increase the effectivecapacitance of the boot capacitor Cb. In other types of circuits havingcharge pumps, any existing dummy metal layer can be put to use in asimilar way to increase the effective capacitance of the boot capacitorCb.

Please refer to FIG. 2 , which is a circuit diagram showing the metalcapacitor C_MET and the MOS capacitor C_MOS connected in parallel.According to the embodiment of the present disclosure, the bootcapacitor Cb includes the metal capacitor C_MET and the MOS capacitorC_MOS.

In the MOS capacitor C_MOS, the gate of the transistor is electricallyconnected to the boot voltage Vb, and the source and drain of thetransistor are electrically connected to the driving clock signal clkd.On the other hand, two terminals of the metal capacitor C_MET receivethe boot voltage Vb and the driving clock signal clkd, respectively.Therefore, the metal capacitor C_MET and the MOS capacitor C_MOS areelectrically connected, in parallel, between the boot voltage Vb and thedriving clock signal clkd. To simplify the term, the boot voltage Vb isdefined as the voltage V1, and the driving clock signal clkd is definedas the voltage V2 hereinafter.

When the metal capacitor C_MET and the MOS capacitor C_MOS are connectedin parallel, the effective capacitance of the boot capacitor Cb isincreased. According to a simulation result, the capacitance of the bootcapacitor Cb is increased with 40% by using the metal capacitor C_MET.Since the metal capacitor C_MET is implemented by a dummy metal layer,no additional area is required. Therefore, the additional capacitancecontributed by the metal capacitor C_MET can reduce the area requiredfor the MOS capacitor C_MOS.

Please refer to FIG. 3 , which is a schematic diagram illustrating anelectrode pattern on the metal layer disposed above the MOS capacitor.The MOS capacitor C_MOS includes polysilicon layers 31 a and 31 c and adiffusion layer 31 b. The details of the manufacturing process of theMOS capacitor C_MOS is not given herein. At least one metal layer MTL isdisposed above the MOS capacitor C_MOS. The metal layer MTL forms themetal capacitor C_MET. In the embodiment, the MOS capacitor C_MOS andthe metal capacitor C_MET has a width of about 20 μm along the x-axisand the y-axis. It is to be noted that the width of the metal layer MTLdepends upon the design parameters, and is not limited to that describedin the embodiments of the present disclosure. The position of the metalcapacitor C_MET is just above the MOS capacitor C_MOS (that is, towardpositive z-axis). The MOS capacitor C_MOS having the layered structureis defined as a substrate hereinafter.

In FIG. 3 , the metal layer MTL includes two electrode sheets ELED1 andELED2. In the specification, it is defined that the electrode (sheet)with the upper right to lower left hatch pattern receives the voltageV1, and the electrode (sheet) with the dot hatch pattern receives thevoltage V2. Accordingly, in FIG. 3 , the electrode sheet ELED1 receivesthe voltage V1, and the electrode sheet ELED2 receives the voltage V2.Since the electrode sheets ELED1 and ELED2 receive different voltages,charges are accumulated close to the gap between the electrode sheetsELED1 and ELED2 to generate parasitic capacitance. Therefore, additionalcapacitance is provided between the electrode sheets ELED1 and ELED2.

In the specification, the separate electrode sheets belonging to asingle metal layer form a capacitor, which is defined as a coplanarcapacitor Ch. The capacitance of the coplanar capacitance Ch is directlyproportional to the overall area of the lateral surfaces, at theopposite sides of the gap, of the two electrode sheets, and is inverselyproportional to the separation distance between the lateral surfaces(that is, gap thickness). Therefore, when the electrode sheets have moreelectrodes and/or the electrodes are arranged more closely, the coplanarcapacitor Ch has higher capacitance.

When the semiconductor circuit includes more than one metal layer, inaddition to the coplanar capacitor Ch involving the separate electrodesheets of the single metal layer, parasitic capacitance may also existbetween electrodes (sheets) belonging to different metal layersreceiving different voltages. The capacitor resulting from differentmetal layers is defined as an inter-layer capacitor Cv.

Taking a memory circuit as an example, four metal layers may be providedabove the MOS capacitor. According to the concept of the presentdisclosure, each of the four metal layers includes two electrode sheetsfor receiving the voltages V1 and V2, respectively. The shape of and thevoltage received by each electrode sheet are designed according to theposition coordinate. For illustration purposes, the followingdescription only describes the relative position of the metal layers andthe electrode sheets, but not further shows the position relationbetween the substrate and the metal layers.

For clearly describing the position relation of the electrode patternsof the electrode sheets and the metal layers, it is defined that thex-axis, the y-axis and the z-axis correspond to the lengthwisedirection, the widthwise direction, and the height direction,respectively. Each metal layer has a unique z-coordinate. It is to benoted that the directions and relative positions may vary with realconditions.

Please refer to FIG. 4 , which is a schematic diagram illustrating thatelectrode sheets are formed of two metal layers, and the capacitance isformed based on the electrode patterns of the electrode sheets accordingto an embodiment of the present disclosure. In this embodiment, twometal layers MTL1 and MLT2, are disposed above the substrate. Concretelyspeaking, the metal layer MTL1 is disposed above the substrate, and themetal layer MTL2 is disposed above the metal layer MTL1. Further, themetal layer MTL1 includes electrode sheets ELED1 and ELED2, and themetal layer MTL2 includes electrode sheets ELED3 and ELED4. Theelectrode sheets ELED1 and ELED3 receive the voltage V1, and theelectrode sheets ELED2 and ELED4 receive the voltage V2.

From the drawing of partial enlargement at the upper right corner, inthe metal layer MTL2, the electrode sheets ELED3 and ELED4 receive thevoltages V1 and V2, respectively, and collectively form the coplanarcapacitor Ch. Similarly, in the metal layer MTL1, the electrode sheetsELED1 and ELED2 receive the voltages V1 and V2, respectively, andcollectively form the coplanar capacitor Ch.

In addition to the coplanar capacitor resulting from each metal layer,an inter-layer capacitor is formed by arranging the electrodes in aspecific manner. For example, when the electrode of the electrode sheetof the metal layer MTL2 receives a different voltage from the electrodeof the electrode sheet of the metal layer MTL1 wherein both theelectrodes have corresponding positions to each other (that is, samex-coordinate and y-coordinate), the two electrodes collectively form theinter-layer capacitor Cv. As the inter-layer capacitor Cv is formed byelectrodes which are vertically overlapped, the inter-layer capacitor Cvcan also be defined as a vertical capacitor.

Considering the two metal layers MTL1 and MTL2, at least a portion ofthe electrode sheet ELED4 is disposed above the electrode sheet ELED1.Since the electrode sheet ELED1 and the electrode sheet ELED4 receivethe voltage V1 and the voltage V2, respectively, the inter-layercapacitor Cv is formed by the overlapping portions of the electrodesheet ELED1 and the electrode sheet ELED4. Similarly, since at least aportion of the electrode sheet ELED3 is disposed above the electrodesheet ELED2, another inter-layer capacitor Cv is formed by theoverlapping portions of the electrode sheet ELED2 and the electrodesheet ELED3.

Please refer to the electrode sheets ELED1, ELED2, ELED3, and ELED4 inFIG. 4 . The electrodes with a heavy border will form the inter-layercapacitors Cv with upper or lower corresponding electrodes (that is,electrodes with greater or smaller z-coordinates). On the other hand,the electrodes with a light border do not form the inter-layercapacitors Cv with upper or lower corresponding electrodes (that is,electrodes with greater or smaller z-coordinates). The details aboutwhether the electrodes at specific positions would form the inter-layercapacitors Cv or not will be given below.

In FIG. 4 , the electrode pattern of the electrode sheet ELED1 resemblesthe electrode pattern of the electrode sheet ELED3, while the electrodepattern of the electrode sheet ELED2 resembles the electrode pattern ofthe electrode sheet ELED4. In other words, in the metal layers MTL1 andMTL2, the electrode sheets ELED1 and ELED3 receive the same voltage V1and have a similar configuration, while the electrode sheets ELED2 andELED4 receive the same voltage V2 and have a similar configuration.

From FIG. 4 , coplanar capacitors Ch and inter-layer capacitors Cv areformed by any proper pairs of the electrode sheets ELED1, ELED2, ELED3,and ELED4. The principle of forming the coplanar capacitors Ch and theinter-layer capacitors Cv with the electrode sheets ELED1, ELED2, ELED3,and ELED4 and the connection relations between the coplanar capacitorsCh and the inter-layer capacitors Cv will be described with reference toFIGS. 5A-5D.

Please refer to FIGS. 5A, 5B, 5C, and 5D, which are schematic diagramsshowing the mutual capacitance between the electrode sheets of the twometal layers. The relative positions of the electrode sheets ELED1,ELED2, ELED3, and ELED4 and the coplanar capacitors Ch and theinter-layer capacitors Cv formed thereby are rearranged and shown inFIG. 5A.

In the metal layer MTL1, since the electrode sheets ELED1 and ELED2receive different voltages, the electrode sheets ELED1 and ELED2collectively form the coplanar capacitor Ch1. Similarly, in the metallayer MTL2, since the electrode sheets ELED3 and ELED4 receive differentvoltages, the electrode sheets ELED3 and ELED4 collectively form thecoplanar capacitor Ch2. Further, focusing on the overlapping portions ofthe metal layers MTL1 and MTL2, the electrode sheets ELED1 and ELED4collectively form the inter-layer capacitor Cv1, and the electrodesheets ELED2 and ELED3 collectively form the inter-layer capacitor Cv2.

Viewing the coplanar capacitors Ch1, Ch2, and the inter-layer capacitorsCv1, Cv2 from the x-z plane in FIG. 5A, the relative positions arerearranged and shown in FIG. 5B. Since both the electrode sheets ELED1and ELED3 receive the voltage V1, the voltage levels on the electrodesheets ELED1 and ELED3 are equal to each other. Therefore, theequivalent circuit of FIG. 5B is simplified as shown in FIG. 5C.Similarly, since both the electrode sheets ELED2 and ELED4 receive thevoltage V2, the voltage levels on the electrode sheets ELED2 and ELED4are equal to each other. Therefore, the equivalent circuit of FIG. 5Cmay be further simplified, as shown in FIG. 5D.

According to the description with reference to FIGS. 5A-5D, properdesign of the electrode patterns of the electrode sheets ELED1, ELED2,ELED3, and ELED4 of the metal layers MTL1 and MTL2 can generate multiplecapacitors (including the inter-layer capacitors Cv and the coplanarcapacitors Ch) connected in parallel. Therefore, the parasiticcapacitance effect resulting from especially designed electrode patternson the dummy metal layers can be used to form the metal capacitor C_METin FIG. 2 to increase the effective capacitance of the boot capacitorCb.

The electrode sheets ELED1, ELED2, ELED3, and ELED4 shown in FIG. 4 havefewer electrodes than real applications due to the drawing limitation.In an embodiment to be described, in the top view within an area of 20μm*20 μm, each of the metal layers MTL1 and MTL2 includes 38 rowelectrodes parallel to the x-axis. It is to be noted that the area andthe number of the row electrodes depend upon the design parameters, andare not limited to the embodiment. As described above, the closer theelectrodes are, the higher the capacitance is. Therefore, arranging therow electrodes in high density can increase the capacitance of thecoplanar capacitors Ch1 and Ch2.

In the following description, FIGS. 6 and 7 illustrate the electrodepattern of the electrode sheet ELED1; FIGS. 8 and 9 illustrate theelectrode pattern of the electrode sheet ELED2, and FIG. 10 illustratesthe electrode pattern on the metal layer MTL1 after combining theelectrode sheets ELED1 and ELED2.

Please refer to FIG. 6 , which is a schematic diagram illustrating theconfiguration of the electrode sheet ELED1. The electrode sheet ELED1includes a common electrode cmn11 and electrode sets GP11 a and GP11 b.The common electrode cmn11 is directly connected to both of theelectrode sets GP11 a and GP11 b.

Please refer to FIG. 7 , which is a schematic diagram illustrating thecomponents of the electrode pattern of the electrode sheet ELED1. Theelectrode set GP11 a is shown at the left side, the electrode set GP11 bis shown at the right side, and the common electrode cmn11 is shown atthe bottom.

The electrode set GP11 a includes: a main electrode M11 a parallel tothe y-axis and connected to the common electrode cmn11 and a pluralityof branch electrodes br11 a parallel to the x-axis. The branchelectrodes br11 a are of equal length and connected to the mainelectrode M11 a with the left ends. The right ends of the branchelectrodes br11 a extend toward the positive x-axis. The electrode setGP11 b includes: a main electrode M11 b parallel to the y-axis andconnected to the common electrode cmn11, and a plurality of branchelectrodes br11 b parallel to the x-axis. The branch electrodes br11 bare of equal length and connected to the main electrode M11 b with theright ends. The left ends of the branch electrodes br11 b extend towardthe negative x-axis. Therefore, each of the electrode sets GP11 a andGP11 b has the shape of a flat comb. The teeth of the electrode set GP11a extend toward the positive x-axis, and the teeth of the electrode setGP11 b extend toward the negative x-axis.

The common electrode cmn11 is parallel to the x-axis, and two ends ofthe common electrode cmn11 are connected to the bottoms of the mainelectrodes M11 a and M11 b, respectively. The common electrode cmn11 islonger than the branch electrodes br11 a of the electrode set GP11 a andis also longer than the branch electrodes br11 b of the electrode setGP11 b.

Please refer to both FIG. 6 and FIG. 7 . In the electrode sheet ELED1,the branch electrodes br11 a and the branch electrodes br11 b arearranged at different row positions and interleaved in an alternatemanner. When the metal layer MTL1 includes 38 row electrodes in total,the electrode set GP11 a includes 9 branch electrodes br11 a, and theelectrode set GP11 b includes 9 branch electrodes br11 b. The commonelectrode cmn11 is arranged at the first row (y=1); the branchelectrodes br11 a are arranged from the third row at 4-row intervals(y=3, 7, . . . 35); and the branch electrodes br11 b are arranged fromthe 5th row at 4-row intervals (y=5, 9, . . . 37).

Please refer to FIG. 8 , which is a schematic diagram illustrating theconfiguration of the electrode sheet ELED2. The electrode sheet ELED2includes a common electrode cmn12 and a bent electrode bnd12. The commonelectrode cmn12 is parallel to the x-axis, and the bent electrode bnd12is zigzag-shaped (like an upright square wave).

Please refer to FIG. 9 , which is a schematic diagram illustrating thecomponents of the electrode pattern of the electrode sheet ELED2. Thecommon electrode cmn12 is shown at the top, and the bent electrode bnd12is shown at the lower portion.

The common electrode cmn12 is parallel to the x-axis and has a lengthslightly longer than the bent electrode bnd12 along the x-axis. The bentelectrode bnd12 includes a plurality of long electrodes eledL12 and aplurality of short electrodes eledS12 a and eledS12 b. The longelectrodes eledL12 are of equal length and parallel to the x-axis, whilethe left ends of the long electrodes eledL12 are aligned with a straightline, and the right ends of the long electrodes eledL12 are aligned withanother straight line. As shown in FIG. 8 , the long electrodes eledL12are arranged at even-numbered rows (y is an even number).

Please refer to both FIG. 8 and FIG. 9 . The short electrodes eledS12 aand eledS12 b of the bent electrode bnd12 are parallel to the y-axis.Each of the short electrodes eledS12 a and eledS12 b has a head end anda tail end. The short electrodes eledS12 a are connected to the leftends of the long electrodes eledL12 with the head ends, and the tailends, and the short electrodes eledS12 b are connected to the right endsof the long electrodes eledL12 with the head ends and the tail ends.Further, the left end and the right end of one long electrode eledL12are connected to one short electrode eledS12 a and one short electrodeeledS12 b extending toward opposite directions along the y-axis.

For example, the right ends of the long electrodes eledL12 arranged inthe second row, and the fourth row are connected to two ends of theshort electrodes eledS12 b arranged at the right side, respectively.Similarly, the left ends of the long electrodes eledL12 arranged at the4th row and the 6th row are connected to two ends of the shortelectrodes eledS12 a arranged at the left side, respectively. Similarly,the right ends of the long electrodes eledL12 arranged at the 6th row,and the 8th row are connected to two ends of the right-side shortelectrodes eledS12 b, respectively. Similarly, the left ends of the longelectrodes eledL12 arranged in the 8th row, and the 10th row areconnected to two ends of the left-side short electrodes eledS12 a,respectively. Other connection relations of the long electrodes eledL12and the short electrodes eledS12 a and eledS12 b could be derived in asimilar manner and are not particularly described herein.

That is to say, the positions of the left-side short electrodes eledS12a and the right-side short electrodes eledS12 b are alternate along they-axis. Besides, the left-side short electrodes eledS12 a connected tothe long electrode eledL12 arranged at the 36th row is further connectedto the common electrode cmn12 with the head end.

Please refer to FIG. 10 , which is a schematic diagram illustrating thatthe electrode sheet ELED1 in FIG. 6 , and the electrode sheet ELED2 inFIG. 8 are combined to provide the metal layer MTL1. The electrode sheetELED1 in FIG. 6 and the electrode sheet ELED2 in FIG. 8 collectivelyconstitute the metal layer MTL1 in FIG. 10 . The electrode positions ofthe electrode sheets ELED1 and ELED2 of the metal layer MTL1, asillustrated in FIGS. 6, 8, and 10 are listed in Table 1.

TABLE 1 Metal layer Row number MTL1 Electrode type Direction of theelectrode Electrode Electrode set Main y-axis NA sheet GP11a electrodeELED1 M11a (FIGS. 6, Branch x-axis 3, 7, 11, 15, 19, 7) electrode 23,27, 31, 35 br11a Electrode set Main y-axis NA GP11b electrode M11bBranch x-axis 5, 9, 13, 17, 21, electrode 25, 29, 33, 37 br11b Commonelectrode cmn11 x-axis  1 Electrode Common electrode cmn12 x-axis 38sheet Bent Long x-axis 2, 4, 6, 8, 10, 12, ELED2 electrode electrode 14,16, 18, 20, (FIGS. 8, bnd12 eledL12 22, 24, 26, 28, 9) 30, 32, 34, 36Short y-axis NA electrode eledS12a, eledS12b

From Table 1, it is shown that the branch electrodes br11 a and br11 bof the electrode sheet ELED1 receiving the voltage V1 are mainlyarranged at the odd-numbered rows, and the long electrodes eledLl2 ofthe electrode sheet ELED2 receiving the voltage V2 are mainly arrangedat the even-numbered rows. Therefore, the adjacent row electrodes of themetal layer MTL1 can form the coplanar capacitors Ch1.

In the following description, FIGS. 11 and 12 illustrate the electrodepattern of the electrode sheet ELED3; FIGS. 13 and 14 illustrate theelectrode pattern of the electrode sheet ELED4; and FIG. 15 illustratesthe electrode pattern on the metal layer MTL2 after combining theelectrode sheets ELED3 and ELED4 together.

Please refer to FIG. 11 , which is a schematic diagram illustrating theconfiguration of the electrode sheet ELED3. The electrode sheet ELED3includes a common electrode cmn21 and electrode sets GP21 a and GP21 b.The electrode sheet ELED3 is directly connected to both of the electrodesets GP21 a and GP21 b.

Please refer to FIG. 12 , which is a schematic diagram illustrating thecomponents of the electrode pattern of the electrode sheet ELED3. Theelectrode set GP21 a is shown at the left side, the electrode set GP21 bis shown at the right side, and the common electrode cmn21 is shown atthe bottom.

The electrode set GP21 a includes: a main electrode M21 a parallel tothe y-axis and connected to the common electrode cmn21 and a pluralityof branch electrodes br21 a parallel to the x-axis. The branchelectrodes br21 a are of equal length and connected to the mainelectrode M21 a with the left ends. The right ends of the branchelectrodes br21 a extend toward the positive x-axis. The electrode setGP21 b includes: a main electrode M21 b parallel to the y-axis andconnected to the common electrode cmn21, and a plurality of branchelectrodes br21 b parallel to the x-axis. The branch electrodes br21 bare of equal length and connected to the main electrode M21 b with theright ends. The left ends of the branch electrodes br21 b extend towardthe negative x-axis. Therefore, each of the electrode sets GP21 a andGP21 b has the shape of a flat comb. The teeth of the electrode set GP21a extend toward the positive x-axis, and the teeth of the electrode setGP21 b extend toward the negative x-axis.

The common electrode cmn21 is parallel to the x-axis, and two ends ofthe common electrode cmn21 are connected to the bottoms of the mainelectrodes M21 a and M21 b, respectively. The common electrode cmn21 islonger than the branch electrodes br21 a of the electrode set GP21 a andis also longer than the branch electrodes br21 b of the electrode setGP21 b.

Please refer to both FIG. 11 and FIG. 12 . In the electrode sheet ELED3,the branch electrodes br21 a and the branch electrodes br21 b arearranged at different row positions and interleaved in an alternatemanner. When the metal layer MTL2 includes 38 row electrodes in total,the electrode set GP21 a includes 8 branch electrodes br21 a, and theelectrode set GP21 b includes 9 branch electrodes br21 b. The commonelectrode cmn21 is arranged at the first row (y=1); the branchelectrodes br21 a are arranged from the 6th row at 4-row intervals (y=6,10, . . . 34); and the branch electrodes br21 b are arranged from the4th row at 4-row intervals (y=4, 8, . . . 36).

Please refer to FIG. 13 , which is a schematic diagram illustrating theconfiguration of the electrode sheet ELED4. The electrode sheet ELED4includes a common electrode cmn22 and a bent electrode bnd22. The commonelectrode cmn22 is parallel to the x-axis, and the bent electrode bnd22is zigzag-shaped (like an upright square wave).

Please refer to FIG. 14 , which is a schematic diagram illustrating thecomponents of the electrode pattern of the electrode sheet ELED4. Thecommon electrode cmn22 is shown at the top, and the bent electrode bnd22is shown at the lower portion.

The common electrode cmn22 is parallel to the x-axis and has a lengthslightly longer than the bent electrode bnd22 along the x-axis. The bentelectrode bnd22 includes a plurality of long electrodes eledL22 and aplurality of short electrodes eledS22 a and eledS22 b. The longelectrodes eledL22 are of equal length and parallel to the x-axis, whilethe left ends of the long electrodes eledL22 are aligned with a straightline, and the right ends of the long electrodes eledL22 are aligned withanother straight line. As shown in FIG. 13 , the long electrodes eledL22are arranged in the second row, the 38th row, and the odd-numbered rowsare falling between the second row and the 38th row (y=3, 5, . . . 37).

Please refer to both FIG. 13 and FIG. 14 . The short electrodes eledS22a and eledS22 b of the bent electrode bnd22 are parallel to the y-axis.Each of the short electrodes eledS22 a and eledS22 b has a head end anda tail end. The short electrodes eledS22 a are connected to the leftends of the long electrodes eledL22 with the head ends, and the tailends, and the short electrodes eledS22 b are connected to the right endsof the long electrodes eledL22 with the head ends and the tail ends.Further, the left end and the right end of one long electrode eledL22are connected to one short electrode eledS22 a and one short electrodeeledS22 b extending toward opposite directions along the y-axis.

For example, the right ends of the long electrodes eledL12 arranged inthe second row, and the third row are connected to two ends of the shortelectrodes eledS22 b arranged at the right side, respectively.Similarly, the left ends of the long electrodes eledL22 arranged at thethird row and the 5th row are connected to two ends of the shortelectrodes eledS22 a arranged at the left side, respectively. Similarly,the right ends of the long electrodes eledL12 arranged at the 5th row,and the 7th row are connected to two ends of the right-side shortelectrodes eledS22 b, respectively. Similarly, the left ends of the longelectrodes eledL22 arranged at the 7th row, and the 9th row areconnected to two ends of the left-side short electrodes eledS22 a,respectively. Other connection relations of the long electrodes eledL22and the short electrodes eledS22 a and eledS22 b could be derived in asimilar manner and are not particularly described herein.

That is to say, the positions of the left-side short electrodes eledS22a and the right-side short electrodes eledS22 b are alternate along they-axis. Besides, the right-side short electrodes eledS22 b connected tothe long electrode eledL22 arranged at the 37th row is connected to thecommon electrode cmn22 with the head end.

Please refer to FIG. 15 , which is a schematic diagram illustrating thatthe electrode sheet ELED3 in FIG. 11 and the electrode sheet ELED4 inFIG. 13 are combined to provide the metal layer MTL2. The electrodesheet ELED3 in FIG. 11 and the electrode sheet ELED4 in FIG. 13collectively constitute the metal layer MTL2 in FIG. 15 . The electrodepositions of the electrode sheets ELED3 and ELED4 of the metal layerMTL2, as illustrated in FIGS. 11, 13, and 15 are listed in Table 2.

TABLE 2 Metal layer Row number MTL2 Electrode type Direction of theelectrode Electrode Electrode set Main y-axis NA sheet GP21a electrodeELED3 M21a (FIGS. Branch x-axis 6, 10, 14, 18, 11, 12) electrode 22, 26,30, 34 br21a Electrode set Main y-axis NA GP21b electrode M21b Branchx-axis 4, 8, 12, 16, 20, electrode 24, 28, 32, 36 br21b Common electrodecmn21 x-axis  1 Electrode Common electrode cmn22 x-axis 38 sheet BentLong x-axis 2, 3, 5, 7, 9, 11, ELED4 electrode electrode 13, 15, 17, 19,21, (FIGS. bnd22 eledL22 23, 25, 27, 29, 13, 14) 31, 33, 35, 37 Shorty-axis NA electrode eledS22a, eledS22b

From Table 2, it is shown that the branch electrodes br21 a and br21 bof the electrode sheet ELED3 receiving the voltage V1 are mainlyarranged at the even-numbered rows, and the long electrodes eledL22 ofthe electrode sheet ELED4 receiving the voltage V2 are mainly arrangedat the odd-numbered rows. Therefore, the adjacent row electrodes of themetal layer MTL2 can form the coplanar capacitors Ch2.

As described above, such design of the electrode patterns can have themetal layers MTL1 and MTL2 themselves to form the coplanar capacitorsCh1 and Ch2. In addition, the metal layers MTL1 and MTL2 also form theinter-layer capacitors Cv1 and Cv2.

Please refer to FIGS. 6, 7, 13, and 14 , along with Tables 1 and 2. Aslisted in Table 1, in FIGS. 6 and 7 , the branch electrodes br11 a ofthe electrode sheet ELED1 are arranged at the third, 7th, 11th, 15th,19th, 23rd, 27th, 31st, and 35th rows; and the branch electrodes br11 bof the electrode sheet ELED1 are arranged at the 5th, 9th, 13th, 17th,21st, 25th, 29th, 33rd, and 37th rows. As listed in Table 2, in FIGS. 13and 14 , the long electrodes eledL22 of the bent electrode bnd22 of theelectrode sheet ELED4 are arranged at the second row and allodd-numbered rows between the third row and the 37th row. Since themetal layer MTL2 is disposed above the metal layer MTL1, it is shownthat the long electrodes eledL22 of the electrode sheet ELED4 are mainlydisposed above the branch electrodes br11 a of the electrode sheetELED1. In addition, the electrode sheet ELED1 receives the voltage V1and the electrode sheet ELED4 receives the voltage V2. Accordingly, whenthe metal layer MTL2 in FIG. 15 is disposed right above the metal layerMTL1 in FIG. 10 , the two metal layers MTL1 and MTL2 collectively formthe inter-layer capacitors Cv1 within the region corresponding to all ofthe odd-numbered rows between the third row and the 37th row.

Please refer to FIGS. 8, 9, 11, and 12 , along with Tables 1 and 2. Aslisted in Table 1, in FIGS. 8 and 9 , the long electrodes eledL12 of thebent electrode bnd12 of the electrode sheet ELED2 are arranged at theeven-numbered rows (y=2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26,28, 30, 32, 34 and 36). As listed in Table 2, in FIGS. 11 and 12 , thebranch electrodes br21 a of the electrode sheet ELED3 are arranged atthe 6th, 10th, 14th, 18th, 22nd, 26th, 30th and 34th rows; and thebranch electrodes br21 b of the electrode sheet ELED3 are arranged atthe 4th, 8th, 12th, 16th, 20th, 24th, 28th, 32nd, and 36th rows. Sincethe metal layer MTL2 is disposed above the metal layer MTL1, it is shownthat the branch electrodes br21 a and br21 b of the electrode sheetELED3 are completely disposed above the long electrodes eledL12 of theelectrode sheet ELED2. In addition, the electrode sheet ELED2 receivesthe voltage V2 and the electrode sheet ELED3 receives the voltage V1.Accordingly, when the metal layer MTL2 in FIG. 15 is disposed rightabove the metal layer MTL1 in FIG. 10 , the two metal layers MTL1 andMTL2 collectively form the inter-layer capacitors Cv2 within the regioncorresponding to all of the even-numbered rows.

The concepts of the metal layers and the electrode sheets describedabove may be applied to more metal layers. FIG. 16 illustrates anexample of four metal layers. In practice, the number of metal layersdepends on the layer number related to the semiconductor process.

Please refer to FIG. 16 , which is a schematic diagram illustrating thatthe electrode patterns on the multiple metal layers are arranged in analternate manner. For illustration purposes, the electrode positions inthe electrode patterns of the electrode sheets mELED1, mELED2, mELED3,mELED4, mELED5, mELED6, mELED7 and mELED8 of the metal layers mMTL1,mMTL2, mMTL3, and mMTL4 are listed in Table 3.

TABLE 3 Row number Voltage 1 2 3 4 5 6 7 8 9 10 11 12 13 14 MetalElectrode V1 X X X X X X X layer sheet mMTL1 mELED1 Electrode V2 X X X XX X X sheet mELED2 Metal Electrode V1 X X X X X X layer sheet mMTL2mELED3 Electrode V2 X X X X X X X X sheet mELED4 Metal Electrode V1 X XX X X X X layer sheet mMTL3 mELED5 Electrode V2 X X X X X X X sheetmELED6 Metal Electrode V1 X X X X X X layer sheet mMTL4 mELED7 ElectrodeV2 X X X X X X X X sheet mELED8

As described above, the electrode sheets of different metal layerscollectively form the inter-layer capacitors, and the electrode sheetsof each single metal layer collectively form the coplanar capacitor.Therefore, according to the design of the electrode patterns, as shownin FIG. 16 , the electrode sheets mELED1 and mELED2 of the metal layermMTL1 collectively form the coplanar capacitor Ch; the electrode sheetsmELED3 and mELED4 of the metal layer mMTL2 collectively form thecoplanar capacitor Ch; the electrode sheets mELED5 and mELED6 of themetal layer mMTL3 collectively form the coplanar capacitor Ch, and theelectrode sheets mELED7 and mELED8 of the metal layer mMTL4 collectivelyform the coplanar capacitor Ch. In addition, the metal layers mMTL1 andmMTL2 collectively form the inter-layer capacitors Cv; the metal layersmMTL2 and mMTL3 collectively form the inter-layer capacitors Cv, and themetal layers mMTL3 and mMTL4 collectively form the inter-layercapacitors Cv.

In the above embodiments, the electrode sheets receiving the voltage V1have a similar configuration, and the electrode sheets receiving thevoltage V2 have a similar configuration. For example, both the electrodesheet ELED1 of the metal layer MTL1 and the electrode sheet ELED3 of themetal layer MTL2 receive the voltage V1 and each of which includes acommon electrode arranged at the first row and electrode sets.Similarly, both the electrode sheet ELED2 of the metal layer MTL1 andthe electrode sheet ELED4 of the metal layer MTL2 receive the voltage V2and each of which includes a common electrode and a bent electrode. Inpractice, the condition of a similar configuration for a specificreceived voltage is not necessary. For example, in the embodiment withreference to FIG. 17 , the electrode sheets respectively belonging toadjacent metal layers and receiving the same voltage have differentelectrode patterns.

Please refer to FIG. 17 , which is a schematic diagram illustrating thatthe capacitance effect between electrode sheets of two metal layersoccurs based on the electrode patterns of the electrode sheets accordingto another embodiment of the present disclosure. For illustrationpurposes, the electrode positions in the electrode patterns of theelectrode sheets oELED1, oELED2, oELED3, and oELED4 of the metal layersoMTL1 and oMTL2 are listed in Table 4.

TABLE 4 Row number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Metal Electrode X XX X X X X layer sheet oMTL1 oELED1(V1) Electrode X X X X X X X sheetoELED2(V2) Metal Electrode X X X X X X X layer sheet oMTL2 oELED3(V1)Electrode X X X X X X X sheet oELED4(V2)

The electrode patterns and the relative positions of the electrodes ofthe electrode sheets oELED3 and oELED4 of the metal layer oMTL2 in FIG.17 are slightly different from those in FIG. 4 . According to the designof the electrode patterns in FIG. 17 , each of the electrode sheetsoELED1, oELED2, oELED3, and oELED4 receives the corresponding voltage V1or V2, as shown in FIG. 4 . In other words, in the metal layer oMTL1,the electrode sheet oELED1 receives the voltage V1, and the electrodesheet oELED2 receives the voltage V2. On the other hand, in the metallayer oMTL2, the electrode sheet oELED4 receives the voltage V2, and theelectrode sheet oELED3 receives the voltage V1. Therefore, the detailsabout the inter-layer capacitors Cv formed by the electrode sheets ofseparate metal layers and the coplanar capacitors Ch formed by theseparate electrode sheets of the single metal layer are as described inthe above embodiments.

In FIG. 17 , the electrode pattern of the electrode sheet oELED1resembles the electrode pattern of the electrode sheet oELED4, while theelectrode pattern of the electrode sheet oELED2 resembles the electrodepattern of the electrode sheet ELED3. In other words, the electrodesheet oELED1 of the metal layer oMTL1 receiving the voltage V1 has asimilar configuration to the electrode sheet oELED4 of the metal layeroMTL2 receiving the voltage V2. On the other hand, the electrode sheetoELED2 of the metal layer oMTL1 receiving the voltage V2 has a similarconfiguration to the electrode sheet oELED3 of the metal layer oMTL2receiving the voltage V1.

The electrode patterns of the present disclosure could be furthermodified. For example, the electrode patterns could have more sectionsalong the x-axis. The quantities of the bent electrodes and theelectrode sets could be adjusted according to the number of thesections. The arrangement of the electrodes should be adjusted accordingto the quantities of the bent electrodes and the electrode sets. Thefollowing description explains the electrode sheets with multiplesections in one metal layer. In practice, the configuration of theelectrode sheets of other metal layers should be modifiedcorrespondingly. The related design of the electrode patterns of themetal layers is not given verbosely.

Please refer to FIG. 18 , which is a schematic diagram illustrating thatthe electrode sheets of the metal layer s2MTL1 include two sectionsaccording to a further embodiment of the present disclosure. The metallayer s2MTL1 includes electrode sheets s2ELED1, and s2ELED2. FIGS. 19and 20 illustrate the configuration of the electrode sheet s2ELED1, andFIGS. 21 and 22 illustrate the configuration of the electrode sheets2ELED2.

Please refer to FIG. 19 , which is a schematic diagram illustrating theconfiguration of the electrode sheet s2ELED1 in FIG. 18 . The electrodesheet s2ELED1 includes a common electrode s2 cmn 11 and electrode setss2GP11 a, s 2GP11 b and s 2GP11 c. The common electrode s2 cmn 11 isdirectly connected to the electrode sets s2GP11 a, s 2GP11 b and s 2GP11c.

Please refer to FIG. 20 , which is a schematic diagram illustrating thecomponents of the electrode pattern of the electrode sheet s2ELED1 inFIG. 18 . The electrode set s2GP11 a includes a main electrode s2M11 aand a plurality of branch electrodes s2 br 11 a; the electrode sets2GP11 includes a main electrode s2M11 b and a plurality of branchelectrodes s2 br 11 b, and the electrode set s2GP11 c includes a mainelectrode s2M11 c and a plurality of branch electrodes s2 br 11 c 1 ands2 br 11 c 2. The main electrodes s2M11 a, s 2M11 b and s 2M11 c areparallel to the y-axis; and the branch electrodes s2 br 11 a, s 2 br 11b, s 2 br 11 c 1 and s2 br 11 c 2 are parallel to the x-axis.

Each of the electrode sets s2GP11 a and s 2GP11 b has the shape of aflat comb. Their components are similar to those of the electrode setsGP11 a and GP11 b in FIG. 7 , and similar details are not given herein.In addition, the electrode set s2GP11 c has the shape of a fishbone. Thebranch electrodes s2 br 11 c 1 and s2 br 11 c 2 of the electrode sets2GP11 c are arranged at opposite sides of the main electrode s2M11 c,respectively. Therefore, the electrode set s2GP11 c includes more branchelectrodes (s2 br 11 c 1 and s2 br 11 c 2) than each of the electrodeset s2GP11 a (including branch electrodes s2 br 11 a) and s2GP11 b(including branch electrodes s2 br 11 b). Furthermore, the commonelectrode s2 cmn 11 is parallel to the x-axis. Two ends of the commonelectrode s2 cmn 11 are connected to the main electrodes s2M11 a and s2M11 b, respectively, and the middle part of the common electrode s2 cmn11 is connected to the main electrode s2M11 c.

Please refer to FIG. 21 , which is a schematic diagram illustrating theconfiguration of the electrode sheet s2ELED2 in FIG. 18 . The electrodesheet s2ELED2 includes a common electrode s2 cmn 12 and bent electrodess2 bnd 12 a and s 2 bnd 12 b.

Please refer to FIG. 22 , which is a schematic diagram illustrating thecomponents of the electrode pattern of the electrode sheet s2ELED2 inFIG. 18 . The common electrode s2 cmn 12 is parallel to the x-axis. Theelectrode sheet s2ELED2 has mirror symmetry because the bent electrodess2 bnd 12 a and s 2 bnd 12 b are symmetric to each other. The longelectrodes s2 bnd 12 aL of the bent electrode s2 bnd 12 a and the longelectrodes s2 bnd 12 bL of the bent electrode s2 bnd 12 b are equal inquantity and size; the short electrodes s2 bnd 12 aSa of the bentelectrode s2 bnd 12 a and the short electrodes s2 bnd 12 bSb of the bentelectrode s2 bnd 12 b are equal in quantity and size; and the shortelectrodes s2 bnd 12 aSb of the bent electrode s2 bnd 12 a and the shortelectrodes s2 bnd 12 bSa of the bent electrode s2 bnd 12 b are equal inquantity and size.

FIG. 18 illustrates the metal layer s2MTL1 obtained by combining theelectrode sheet s2ELED1 in FIG. 19 and the electrode sheet s2ELED2 inFIG. 21 together. The main electrode s2M11 c divides the metal layers2MTL1 into two sections. The electrode pattern of the electrode sheets2ELED1 has mirror symmetry wherein two portions respectively at x=1,and x=2 are symmetric to each other. Similarly, the electrode pattern ofthe electrode sheet s2ELED2 has mirror symmetry wherein two sections atx=1 and x=2 are symmetric to each other.

Please refer to FIG. 23 , which is a schematic diagram illustrating thatthe electrode sheets of the metal layer s2MTL1′ include two sectionsaccording to a further embodiment of the present disclosure. The metallayer s2MTL1′ includes electrode sheets s2ELED1′ and s2ELED2′. FIGS. 24and 25 illustrate the configuration of the electrode sheet s2ELED1′, andFIGS. 26 and 27 illustrate the configuration of the electrode sheets2ELED2′.

Please refer to FIG. 24 , which is a schematic diagram illustrating theconfiguration of the electrode sheet s2ELED1′ in FIG. 23 . The electrodesheet s2ELED1′ includes a common electrode s2 cmn 11′ and electrode sets2GP11 a′, s2GP11 b′ and s2GP11 c′.

Please refer to FIG. 25 , which is a schematic diagram illustrating thecomponents of the electrode pattern of the electrode sheet s2ELED1′ inFIG. 23 . The electrode set s2GP11 a′ includes a main electrode s2M11 a′and a plurality of branch electrodes s2 br 11 a′; the electrode sets2GP11 b′ includes a main electrode s2M11 b′ and a plurality of branchelectrodes s2 br 11 b′; and the electrode set s2GP11 c′ includes a mainelectrode s2M11 c′ and a plurality of branch electrodes s2 br 11 c 1′and s2 br 11 c 2′. The main electrodes s2M11 a′, s2M11 b′ and s2M11 c′are parallel to the y-axis, and the branch electrodes s2 br 11 a′, s2 br11 b′, s2 br 11 c 1′ and s2 br 11 c 2′ are parallel to the x-axis.

Each of the electrode sets s2GP11 a′ and s2GP11 b′ has the shape of aflat comb. Their components are similar to those of the electrode setsGP21 a and GP21 b in FIG. 11 , and similar details are not given herein.In addition, the electrode set s2GP11 c′ has the shape of a fishbone.The branch electrodes s2 br 11 c 1′ and s2 br 11 c 2′ of the electrodeset s2GP11 c′ are arranged at opposite sides of the main electrode s2M11c′, respectively. Therefore, the electrode set s2GP11 c′ includes morebranch electrodes (s2 br 11 c 1′ and s2 br 11 c 2′) than each of theelectrode sets s2GP11 a′ (including branch electrodes s2 br 11 a′) ands2GP11 b′ (including branch electrodes s2 br 11 b′). Furthermore, thecommon electrode s2 cmn 11′ is parallel to the x-axis. Two ends of thecommon electrode s2 cmn 11′ are connected to the main electrodes s2M11a′ and s2M11 b′, respectively, and the middle part of the commonelectrode s2 cmn 11′ is connected to the main electrode s2M11 c′.

Please refer to FIG. 26 , which is a schematic diagram illustrating theconfiguration of the electrode sheet s2ELED2′ in FIG. 23 . The electrodesheet s2ELED2′ includes a common electrode s2 cmn 12′ and bentelectrodes s2 bnd 12 a′ and s2 bnd 12 b′.

Please refer to FIG. 27 , which is a schematic diagram illustrating thecomponents of the electrode pattern of the electrode sheet s2ELED2′ inFIG. 23 . The common electrode s2 cmn 12′ is parallel to the x-axis. Thebent electrode s2 bnd 12 a′ has an identical shape to the bent electrodes2 bnd 12 b′, and the bent electrodes s2 bnd 12 a′ and s2 bnd 12 b′ arearranged side by side. The long electrodes s2 bnd 12 aL′ of the bentelectrode s2 bnd 12 a′ and the long electrodes s2 bnd 12 bL′ of the bentelectrode s2 bnd 12 b′ are equal in quantity and size; the shortelectrodes s2 bnd 12 aSa′ of the bent electrode s2 bnd 12 a′ and theshort electrodes s2 bnd 12 bSa′ of the bent electrode s2 bnd 12 b′ areequal in quantity and size; and the short electrodes s2 bnd 12 aSb′ ofthe bent electrode s2 bnd 12 a′ and the short electrodes s2 bnd 12 bSb′of the bent electrode s2 bnd 12 b′ are equal in quantity and size.

FIG. 23 illustrates the metal layer s2MTL1′ obtained by combining theelectrode sheet s2ELED1′ in FIG. 24 and the electrode sheet s2ELED2′ inFIG. 26 together. The main electrode s2M11 c′ divides the metal layers2MTL1′ into two sections. In the electrode pattern of the electrodesheet s2ELED1′, the shape of one section at x=1 is identical to theshape of the other section at x=2. Similarly, in the electrode patternof the electrode sheet s2ELED2′, the shape of one section at x=1 isidentical to the shape of the other section at x=2.

Please refer to FIG. 28 , which is a schematic diagram illustrating thatthe electrode sheets of the metal layer s4MTL1 include four sectionsaccording to a further embodiment of the present disclosure. The metallayer s4MTL1 includes electrode sheets s4ELED1 and s4ELED2. Theelectrode sheet s4ELED1 includes a common electrode and four electrodesets, and the electrode sheet s4ELED2 includes a common electrode andfour bent electrodes. In the electrode pattern, two sections at x=1 andx=2 are symmetric to each other, and two sections at x=3 and x=4 aresymmetric to each other. Further, the combination of the left twosections at x=1 and x=2 of the electrode pattern is symmetric to thecombination of the right two sections at x=3 and x=4 of the electrodepattern and vice versa.

Please refer to FIG. 29 , which is a schematic diagram illustrating thatthe electrode sheets of the metal layer s4MTL1′ includes four sectionsaccording to a further embodiment of the present disclosure. The metallayer s4MTL1′ includes electrode sheets s4ELED1′ and s4ELED2′. Theelectrode sheet s4ELED1′ includes a common electrode and four electrodesets, and the electrode sheet s4ELED2′ includes a common electrode andfour bent electrodes. Four sections at x=1, 2, 3, and 4 of the electrodepattern are equal in shape.

Based on the description, the relations of the section number (X) andthe quantities of the electrode set(s), the common electrode, and thebent electrode(s) are listed in Table 5.

TABLE 5 Electrode sheet ELED1 Electrode sheet ELED2 Section commoncommon bent number (X) electrode set electrode electrode electrode X = 12 1 1 1 (FIGS. 6~15) left: flat comb right: flat comb X = 2 3 1 1 2(FIGS. 18~27) left: flat comb right: flat comb middle: fishbone X = 4 51 1 4 (FIGS. 28, 29) left: flat comb right: flat comb middle: fishbone*2

The electrode sets and the bent electrodes increase with the sectionnumber. Corresponding to X sections, the electrode sheet ELED1 includes(X+1) electrode sets, and the electrode sheet ELED2 includes X bentelectrodes. Each of the electrode sheets ELED1 and ELED2 still includesjust one common electrode, which is not changed with the section number.As described above, the electrode patterns should be modified inresponse to the section number. Such modified electrode patterns arevariants of the present disclosure in various applications, and detailsare not particularly given herein.

To sum up, the present disclosure designs specific electrode patterns ondummy metal layers to generate parasitic capacitance. Such a method ofmodifying the configuration of the electrode sheets ELED1 and ELED2 ofthe metal layer MTL1 and the configuration of the electrode sheets ELED3and ELED4 of the metal layer MTL2 provides a metal capacitor C_METconnected to the MOS capacitor C_MOS in parallel. The use of the dummymetal layers together with the parasitic capacitance effect increasesthe capacitance of the boot capacitor Cb efficiently.

While the invention has been described by way of example and in terms ofthe preferred embodiment(s), it is to be understood that the inventionis not limited thereto. On the contrary, it is intended to cover variousmodifications and similar arrangements and procedures, and the scope ofthe appended claims therefore should be accorded the broadestinterpretation so as to encompass all such modifications and similararrangements and procedures.

What is claimed is:
 1. A metal capacitor comprising: a first metal layerdisposed above a substrate, comprising: a first electrode sheet,comprising: a first common electrode parallel to a first direction; afirst electrode set comprising: a first main electrode parallel to asecond direction and connected to the first common electrode; and aplurality of first branch electrodes parallel to the first direction,wherein each of the plurality of first branch electrodes has a first endand a second end, and the first end of each first branch electrode isconnected to the first main electrode, wherein the first commonelectrode is longer than each first branch electrode, and the firstcommon electrode is placed at a side of the plurality of first branchelectrodes; and a second electrode sheet, comprising: a second commonelectrode parallel to the first direction; and a first bent electrode,comprising: a plurality of first long electrodes parallel to the firstdirection and arranged in a column along the second direction, each ofthe plurality of first long electrodes having a first end and a secondend; and a plurality of first short electrodes parallel to the seconddirection, a first one of the plurality of first short electrodes beingconnected to the second common electrode, wherein a first portion of theplurality of first short electrodes of the first bent electrode areconnected to the first ends of the plurality of first long electrodes ofthe first bent electrode, and a second portion of the plurality of firstshort electrodes of the first bent electrode are connected to the secondends of the plurality of first long electrodes of the first bentelectrode, and a second metal layer disposed above the first metallayer, wherein a first coplanar capacitor is collectively formed betweenthe first electrode sheet and the second electrode sheet, and a firstvertical capacitor is formed between the first electrode sheet and thesecond metal layer.
 2. The metal capacitor according to claim 1, whereinlengths of the plurality of first branch electrodes are equivalent. 3.The metal capacitor according to claim 1, wherein the first electrodesheet further comprises: a second electrode set, comprising: a secondmain electrode parallel to the second direction and connected to thefirst common electrode; and a plurality of second branch electrodesparallel to the first direction, wherein each of the plurality of secondbranch electrodes has a first end and a second end, and the second endof each second branch electrode is connected to the second mainelectrode, wherein the second end of each first branch electrode extendstoward the second main electrode, and the first end of each secondbranch electrode extends toward the first main electrode, wherein thefirst common electrode is longer than each second branch electrode, andthe first common electrode is placed at a side of the plurality ofsecond branch electrodes.
 4. The metal capacitor according to claim 3,wherein lengths of the plurality of second branch electrodes areequivalent.
 5. The metal capacitor according to claim 3, wherein thefirst portion of the plurality of first short electrodes of the firstbent electrode are aligned with a first straight line along the seconddirection, and the second portion of the plurality of first shortelectrodes of the first bent electrode are aligned with a secondstraight line along the second direction, the first portion of theplurality of first short electrodes and the second portion of theplurality of first short electrodes being alternate along the seconddirection.
 6. The metal capacitor according to claim 1, wherein thesecond common electrode is longer than each first long electrode.
 7. Themetal capacitor according to claim 1, wherein the first main electrodeis closer to the first ends of the plurality of first long electrodesthan the second main electrode, and the second main electrode is closerto the second ends of the plurality of first long electrodes than thefirst main electrode.
 8. The metal capacitor according to claim 1,wherein the second metal layer comprises: a third electrode sheet; and afourth electrode sheet, wherein the third electrode sheet and the fourthelectrode sheet collectively form a second coplanar capacitor, whereinat least a portion of the fourth electrode sheet is arranged above thefirst electrode sheet, and the first electrode sheet and the fourthelectrode sheet collectively form the first vertical capacitor, whereinat least a portion of the third electrode sheet is arranged above thesecond electrode sheet, and the second electrode sheet and the thirdelectrode sheet collectively form a second vertical capacitor, whereinthe first electrode sheet and the third electrode sheet receive a firstvoltage, the second electrode sheet and the fourth electrode sheetreceive a second voltage, and the first coplanar capacitor, the secondcoplanar capacitor, the first vertical capacitor and the second verticalcapacitor are connected in parallel.
 9. The metal capacitor according toclaim 8, wherein the third electrode sheet comprises: a third commonelectrode parallel to the first direction; and a third electrode setcomprising: a third main electrode parallel to the second direction andconnected to the third common electrode; and a plurality of third branchelectrodes parallel to the first direction, wherein each of theplurality of third branch electrodes has a first end and a second end,and the first end of each third branch electrode is connected to thethird main electrode, wherein the third common electrode is longer thaneach third branch electrode, and the third common electrode is placed ata side of the plurality of third branch electrodes.
 10. The metalcapacitor according to claim 9, wherein the third electrode sheetfurther comprises: a fourth electrode set, comprising: a fourth mainelectrode parallel to the second direction and connected to the thirdcommon electrode; and a plurality of fourth branch electrodes parallelto the first direction, wherein each of the plurality of fourth branchelectrodes has a first end and a second end, and the second end of eachfourth branch electrode is connected to the fourth main electrode,wherein the second end of each third branch electrode extends toward thefourth main electrode, and the first end of each fourth branch electrodeextends toward the third main electrode, wherein the third commonelectrode is longer than each fourth branch electrode, and the thirdcommon electrode is placed at a side of the plurality of fourth branchelectrodes.
 11. The metal capacitor according to claim 10, wherein thethird main electrode is disposed right above the first main electrode;and the fourth main electrode is disposed right above the second mainelectrode.
 12. The metal capacitor according to claim 10, wherein theplurality of third branch electrodes and the plurality of fourth branchelectrodes are disposed right above the plurality of first longelectrodes of the first bent electrode.
 13. The metal capacitoraccording to claim 9, wherein the fourth electrode sheet comprises: afourth common electrode parallel to the first direction; and a secondbent electrode comprising: a plurality of second long electrodesparallel to the first direction and arranged in a column along thesecond direction, each of the plurality of second long electrodes havinga first end and a second end; and a plurality of second short electrodesparallel to the second direction, a first one of the plurality of secondshort electrodes being connected to the fourth common electrode, whereina first portion of the plurality of second short electrodes of thesecond bent electrode are aligned with a third straight line secondalong the second direction, and a second portion of the plurality ofsecond short electrodes of the second bent electrode are aligned with afourth straight line along the second direction, the first portion ofthe plurality of second short electrodes and the second portion of theplurality of second short electrodes being alternate along the seconddirection, wherein the first portion of the plurality of second shortelectrodes of the second bent electrode are connected to the first endsof the plurality of second long electrodes of the second bent electrode,and the second portion of the plurality of second short electrodes ofthe second bent electrode are connected to the second ends of theplurality of second long electrodes of the second bent electrode. 14.The metal capacitor according to claim 13, wherein the plurality ofsecond long electrodes of the second bent electrode are disposed rightabove the plurality of first branch electrodes and the plurality ofsecond branch electrodes.
 15. The metal capacitor according to claim 8,wherein the third electrode sheet comprises: a fifth common electrodeparallel to the first direction; a third bent electrode comprising: aplurality of third long electrodes parallel to the first direction andarranged in a column along the second direction, each of the pluralityof third long electrodes having a first end and a second end; and aplurality of third short electrodes parallel to the second direction, afirst one of the plurality of third short electrodes being connected tothe fifth common electrode, wherein a first portion of the plurality ofthird short electrodes of the third bent electrode are aligned with afifth straight line second along the second direction, and a secondportion of the plurality of third short electrodes of the third bentelectrode are aligned with a sixth straight line along the seconddirection, the first portion of the plurality of third short electrodesand the second portion of the plurality of third short electrodes beingalternate along the second direction, wherein the first portion of theplurality of third short electrodes of the third bent electrode areconnected to the first ends of the plurality of third long electrodes ofthe third bent electrode, and the second portion of the plurality ofthird short electrodes of the third bent electrode are connected to thesecond ends of the plurality of third long electrodes of the third bentelectrode.
 16. The metal capacitor according to claim 15, wherein thefourth electrode sheet further comprises: a sixth common electrodeparallel to the first direction; and a fifth electrode set comprising: afifth main electrode parallel to the second direction and connected tothe sixth common electrode; and a plurality of fifth branch electrodesparallel to the first direction, wherein each of the plurality of fifthbranch electrodes has a first end and a second end, and the first end ofeach fifth branch electrode is connected to the fifth main electrode,wherein the sixth common electrode is longer than each fifth branchelectrode, and the sixth common electrode is placed at a side of theplurality of fifth branch electrodes.
 17. The metal capacitor accordingto claim 16, wherein the fourth electrode sheet further comprises: asixth electrode set, comprising: a sixth main electrode parallel to thesecond direction and connected to the sixth common electrode; and aplurality of sixth branch electrodes parallel to the first direction,wherein each of the plurality of sixth branch electrodes has a first endand a second end, and the second end of each sixth branch electrode isconnected to the sixth main electrode, wherein the second end of eachfifth branch electrode extends toward the sixth main electrode, and thefirst end of each sixth branch electrode extends toward the fifth mainelectrode, wherein the sixth common electrode is longer than each sixthbranch electrode, and the sixth common electrode is placed at a side ofthe plurality of sixth branch electrodes.
 18. A metal capacitorcomprising: at least one metal layer disposed above ametal-oxide-semiconductor capacitor, comprising: a first electrode sheetreceiving a first voltage, comprising: a first common electrode parallelto a first direction; and a first electrode set comprising: a first mainelectrode parallel to a second direction and connected to the firstcommon electrode; and a plurality of first branch electrodes parallel tothe first direction, wherein each of the plurality of first branchelectrodes has a first end and a second end, and the first end of eachfirst branch electrode is connected to the first main electrode, whereinthe first common electrode is longer than each first branch electrode,and the first common electrode is placed at a side of the plurality offirst branch electrodes; and a second electrode sheet receiving a secondvoltage, wherein the first electrode sheet and the second electrodesheet collectively form a coplanar capacitor, and the second electrodesheet comprises: a second common electrode parallel to the firstdirection; and a first bent electrode, comprising: a plurality of firstlong electrodes parallel to the first direction and arranged in a columnalong the second direction, each of the plurality of first longelectrodes having a first end and a second end; and a plurality of firstshort electrodes parallel to the second direction, a first one of theplurality of first short electrodes being connected to the second commonelectrode, wherein a first portion of the plurality of first shortelectrodes of the first bent electrode are connected to the first endsof the plurality of first long electrodes of the first bent electrode,and a second portion of the plurality of first short electrodes of thefirst bent electrode are connected to the second ends of the pluralityof first long electrodes of the first bent electrode.
 19. The metalcapacitor according to claim 18, wherein the first electrode sheetfurther comprises: a second electrode set, comprising: a second mainelectrode parallel to the second direction and connected to the firstcommon electrode; and a plurality of second branch electrodes parallelto the first direction, wherein each of the plurality of second branchelectrodes has a first end and a second end, and the second end of eachsecond branch electrode is connected to the second main electrode,wherein the second end of each first branch electrode extends toward thesecond main electrode, and the first end of each second branch electrodeextends toward the first main electrode, wherein the first commonelectrode is longer than each second branch electrode, and the firstcommon electrode is placed at a side of the plurality of second branchelectrodes.
 20. The metal capacitor according to claim 19, whereinlengths of the plurality of first branch electrodes are equivalent, andlengths of the plurality of second branch electrodes are equivalent.